Usleep() for Windows (C#) + set timer resolution to lowest possible supported by system

Usleep.cs

using System;
using System.Runtime.InteropServices;

public static class Utility
{
	static int ntCurrentResolution = 0;
	public static void Usleep(ulong time)
	{
		if (ntCurrentResolution == 0)
			NtSetTimerResolution(1, true, out ntCurrentResolution);

		IntPtr timer = CreateWaitableTimer(IntPtr.Zero, true, null);

		// negative values are for relative time
		long period = -(10 * (long)time);

		SetWaitableTimer(timer, ref period, 0, IntPtr.Zero, IntPtr.Zero, false);

		WaitForSingleObject(timer, 0xFFFFFFFF);
		CloseHandle(timer);
	}
			
	[DllImport("ntdll.dll")]
	static extern int NtSetTimerResolution(int DesiredResolution, bool SetResolution, out int CurrentResolution);
	
	[DllImport("kernel32.dll")]
	static extern IntPtr CreateWaitableTimer(IntPtr lpTimerAttributes, bool bManualReset, string lpTimerName);
	
	[DllImport("kernel32.dll")]
	static extern bool SetWaitableTimer(IntPtr hTimer, ref long pDueTime, int lPeriod, IntPtr pfnCompletionRoutine, IntPtr lpArgToCompletionRoutine, bool fResume);
	
	[DllImport("kernel32.dll", SetLastError = true, ExactSpelling = true)]
	static extern Int32 WaitForSingleObject(IntPtr Handle, uint Wait);
	
	[DllImport("kernel32.dll", SetLastError = true, CallingConvention = CallingConvention.Winapi, CharSet = CharSet.Auto)]
	[return: MarshalAs(UnmanagedType.Bool)]
	static extern bool CloseHandle(IntPtr hObject);
}

Usleep_Test.cs

using System;
using System.Diagnostics;

public static class Program
{
	[STAThread]
	static void Main()
	{
		Stopwatch sw = Stopwatch.StartNew();
		
		int times = 1000;
		// Utility.Usleep(1) sleeps at lowest possible amount of time
		for (int i = 0; i < times; i++)
			Utility.Usleep(1);
		
		sw.Stop();
		
		Console.WriteLine((sw.Elapsed.TotalMilliseconds/times).ToString("0.00"));
	}
}